Ignition distributor



Aug. 3, 1965 c. L. DUSENBERRY ETAL IGNITION DISTRIBUTOR 2 Sheets-Sheet 1Filed June 16, 1961 INVENTORS (War/es Z. Dusezzberzy A 3, 1965 c. L.DUSENBERRY ETAL 3,193,974

IGNITION DISTRIBUTOR 2 Sheets-Sheet 2 Filed June 16, 1961 mvamoas (20246: 1. Dusewberzy Harry G. diff/Hanson 5r 77951)? ATTORNEY UnitedStates Patent 3,198,974 IGNITION DISTRIBUTOR Charles L. Dusenherry,Chesterfieid, and Harry A. Williamson, Anderson, Ind, assignors toGeneral Motors Corporation, Detroit, Mich a corporation of DelawareFiled June 16, 1961, Ser. No. 126,406 19 Claims. (Cl. 316-70) Thisinvention relates to a timing mechanism for controlling the ignitiontiming of an internal combustion engine.

One of the objects of this invention is to provide an ignition timingapparatus that is capable of developing pulses of voltage that may betimed in accordance with the speed and load conditions of an engine onwhich the timing apparatus is used.

Another object of this invention is to provide an ignition timing devicewherein a permanent magnet and coil Winding are mounted on a shiftabletiming plate and wherein a rotor formed of magnetic material controlsthe flux path of magnetic flux that is developed by the permanent magnetand which induces a pulsating voltage in the coil winding.

Still another object of this invention is to provide an ignition timingdevice which includes a shaft that carries a rotor formed of magneticmaterial, there being a timing plate provided that carries a permanentmagnet and a coil winding assembly which is shiftable by a vacuum unit,the rotor being adjustable relative to the shaft by a centrifugaladvance mechanism that is driven by the shaft.

Further objects and advantages of the present invention will be apparentfrom the following description, reference being had to the accompanyingdrawings wherein preferred embodiments of the present invention areclearly shown.

In the drawings:

FIGURE 1 is a sectional view of an ignition timer taken along line 11 ofFIGURE 3.

FIGURE 2 is a sectional view of an ignition timer made in accordancewith this invention and taken along line 22 of FIGURE 3.

*FIGURE 3 is a vertical sectional view of an ignition timer made inaccordance with this invention and taken along line 3-3 of FIGURE 1.

Referring now to the drawings and more particularly to FIGURE 3, thereference numeral designates the base of a distributor which may beformed of any suitable metal material. The base 10 may be for exampleformed of cast iron or could 'be formed of die cast aluminum. The baseIt has a central bore 12 which accommodates the shaft designated byreference numeral 14. The shaft 14 is journalled for rotation inbearings 16 and 18, th bearing 18 having a portion 20 which projectsabove the top end of the distributor base 10. A gear 22 is connectedwith the shaft 14 and this gear is adapted to mesh with the gear that isdriven by a cam shaft of an engine on which an ignition timer is used.

The base It) is formed with a plurality of pockets 24 which receive asuitable permanent lubricating material designated by reference numeral26. The top end of these pockets is closed by a lubricant seal 28 and afelt washer 30.

The ignition timer of this invention includes an annular timing plate 32which is secured to an annular bearing member 34. It can be seen thatthe bearing member 34 is journalled on the portion 20 of bearing 18 andit also can be seen that the timing plate 32 slides on an upstandingportion 36 of the base 10. The timing plate 32 is therefore rotatablewith respect to the fixed bearing 18 and can rotate around the axis ofthe shaft 14. The timing plate 32 is shifted by a conventional vacuummotor 3,198,974 Patented Aug. 3, 1965 G3 which has the usual spring 40and a diaphragm 42. The diaphragm 42 is connected with an actuating rod44, the end of which is connected with the timing plate 32. A pipe 45 isconnected with the interior of the vacuum motor 38 and is adapted to beconnected with the intake manifold of the engine upon which the ignitiontimer is used.

The timing plate 32 carries a magnetic pick-up assembly which isdesignated in its entirety by reference numeral 46. This magneticpick-up assembly 46 comprises identical pole pieces 48 and 50 which areannular in configuration. As is best illustrated in FIGURE 1, the polepieces have V-shaped projections which project radially inwardly. Theprojections on pole piece 48 are designated by reference numeral 52 andit is understood that the pole piece 50 has identical projections whichare aligned with the projections 52 illustrated in FIGURE 1.

The pole pieces 48 and 50 are disposed on opposite sides of an annularpermanent magnet 54 which is of the ceramic type and may be for examplea ferrite permanent magnet. This permanent magnet could of course takevarious other forms and be made up of various compositions. Positionedbetween the pole piece 50 and the timing plate 32 is an annularnon-magnetic spacer member 5'6 which may be for example formed of brassmaterial. A coil winding '58 wound on a spool 60 that is formed ofinsulating material is positioned between the pole pieces 48 and 5t) andinwardly of the permanent magnet 54. The outer peripheral edge of thecoil winding axially abuts the inner surface of the permanent magnet 54and the parts of the magnetic assembly 46 are held together by the screwfasteners 62 and 64. The screw fasteners 62 and 64 pass through openingsformed in the pole pieces 48 and 50 and pass through notches formed inthe permanent magnet 54. The fasteners 62 and 64 likewise pass throughnotches formed in a spacer 56 and are threaded into suitable threadedopenings in the timing plate 32. It thus is seen that as the timingplate 32 rotates, the entire magnetic assembly 46 rotates therewith.

The ignition timer of this invention is provided with a centrifugaladvance mechanism to vary the timing of the voltage pulses induced inthe coil winding 58. To this end, a weight plate 66 is provided which isconnected with a soft iron rotor generally designated by reference 11-meral 68. This soft iron rotor 68 is journalled for rotation on theshaft 14 and has four projecting arms or poles designated respectivelyby reference numerals 70, 72, 74 and 76. It can be seen that the weightplate 66 and th rotor member 68 will move together and that they canrotate relative to the shaft 14 due to the fact that the section 78 ofthe rotor is journalled on the shaft 14.

The centrifugal advance mechanism includes a cam plate member 80 whichis fixed to the top end of the shaft 14. This cam plate member 80carries posts 82 and 84. The weight plate 66 carries posts 86 and 88upon which are journalled the flyweights 90 and 92. A spring 94 connectsposts 84 and 88 and in a similar fashion spring 96 connects posts 82 and86. It can be seen that rotor 68 will be adjusted relative to the shaft14 as the flyweights 9t) and 92 are thrown outwardly by centrifugalforce. This will provide a centrifugal advance adjustment for theignition timer as will become more readily apparent hereinafter.

The weight base 66 drives a distributor rotor generally designated byreference numeral 98 which is formed of a suitable insulating materialand which ha an electrode which cooperates with the circumferentiallyspaced electrode 162 and the central electrode 104 of cap 166. Thedistributor cap 106 is supported by the base 10 of the distributor in amanner Well known to those skilled in the art.

The ignition timer of this invention will develop pulses of voltage inthe coil winding 58 as the rotor 68 is driven al e raby the shaft 14.These pulses of voltage will be timed both in accordance with the engineload conditions and in accordance with engine speed conditions. Thepulses of voltage are adapted to control an ignition system of the typeillustrated in copending application S.N. 95,161 filed on March 13,1961, now patent 3,087,001 and assignec to the assignee of thisinvention. In that application, the pulses of voltage generated in thepick-up coil are used to control the conductivity of a transistor whichin turn controls the current flow to the primary winding of an ignitioncoil. It will of course be appreciated that other systems could be usedwith the ignition timer of this invention as long as they can becontrolled by timed voltage pulses.

It will be appreciated that the permanent magnet 54 will set up a flowof magnetic flux that will for example pass through the pole piece 4-3,then through the rotor 63, and then back to the pole piece 54 and thenback to an opposite side of the permanent magnet 54. This flow ofmagnetic flux will link with the coil winding 58 to cause a voltage tobe induced in this coil winding. It can be seen from an inspection ofFIGURE 1 that flux will fiow in the magnetic circuit when the arms orteeth 70-76 are lined up with corresponding teeth 52 on pole piece 48with the teeth on the pole piece 5% Thus when the teeth on the rotor 68are in alignment with the teeth on the pole pieces, a magnetic circuitis completed which will cause a flow of magnetic flux from the permanentmagnet 54. As the rotor 68 rotates, the time Will come when the teeth7046 are not aligned with any of the teeth on the pole pieces 48 and 50and the flow of magnetic flux is then abruptly cut off. This change inmagnetic flux will cause pulses of voltage to be induced in the coilwinding 58 and there will be eight pulses of voltage for every completerevolution of the rotor 68.

The pulses of voltage will be timed both in accordance with the shiftingof the timing plate 52 and in accordance with the speed of rotation ofthe shaft 14. The vacuum unit 38 will of course shift the timing plate32 to vary the timing of the pulses of voltage in accordance with theamount of vacuum that is applied to the pipe 45. This pipe is of courseconnected with the intake manifold of the engine. The centrifugaladvance mechanism will adjust the rotor 6:; relative to the shaft 14 totherefore also vary the timing of the voltage pulses in accordance withthe speed of rotation of the shaft 14. The ignition timer is thuscapable of providing timed ignition pulses both in accordance with thevacuum conditions in the vacuum unit 38 and in accordance with the speedof the shaft 14.

While the embodiments of the present invention as herein disclosed,constitute a preferred form, it is to be understood that other formsmight be adopted.

What is claimed is as follows:

1. An ignition timer comprising, a base member, a timing plate supportedby said base member, a permanent magnet and coil winding supported bysaid timing plate, pole piece means formed of magnetic material engagingopposite ends of said permanent magnet and said coil winding, a shaftrotatable in said base, and a rotor formed of magnetic material carriedby said shaft adjacent said pole piece means, said rotor member varyingan air gap formed between it and one of said pole piece means as itrotates.

2. An ignition timer comprising, a base member, a shaft rotatable withrespect to said base member, a timing plate adjustable with respect tosaid base member, a. vacuum unit for adjusting said timing plate, amagnetic assembly supported by said timing plate including a fluxgenerating means and a coil winding, and a rotor formed of magneticmaterial rotatably driven by said shaft and swinging in close proximityrelative to said magnetic assembly.

3. An ignition timer comprising, a base member, a timing plate, a shaftjournalled for rotation with respect to said base member, a magneticassembly including a flux generating means and a coil winding supportedby said timing plate, a rotor member formed of magnetic materialrotatably driven by said shaft relative to said magnetic assembl and acentrifugal advance mechanism driven by said shaft for adjusting saidrotor member relative to said shaft.

4. An ignition timing device comprising, a base member, a haftjournalled for rotation in said base member, a timing plate shiftablerelative to said base member, a vacuum unit supported by said basemember for shifting said timing plate, a magnetic assembly carried bysaid timin plate including a permanent magnet and a coil winding, arotor member formed of magnetic material driven by said shaft andswinging in close proximity relative to said magnetic assembly wherebyvoltages are induced in said coil winding as said rotor rotates, and acentrifugal advance mechanism driven by said shaft for adjusting saidrotor member relative to said shaft.

5. An ignition timer comprising, a base member, a timing plate shiftablerelative to said base member, a vacuum unit for shifting said timingplate, a magnetic assembly including first and second pole pieces havingradially projecting teeth, an annular permanent magnet disposed betweensaid pole pieces, a coil Winding disposed between said pole pieces, aspacer member formed of non-magnetic material spacing one of said polepieces from said timing plate, fastener means for securing said polepieces, said permanent magnet, said coil winding and non-magnetic spacermember to said timing plate, a shaft journalled for rotation in saidbase member, and a rotor member formed of magnetic material driven bysaid shaft and rotating in close proximity relative to the inwardlyprojecting teeth of said pole pieces, said rotor member having teeththat are aligned with the teeth of said pole pieces in certainpredetermined positions of said rotor.

6. An ignition timer comprising, a base member, a timing plate shiftablerelative to said base member, a vacuum unit for shifting said timingplate, a magnetic assembly carried by said timing plate, said magneticassembly including first and second pole pieces each having radiallyinwardly extending teeth, a permanent magnet disposed between andengaging said pole pieces, a coil winding positioned between said polepieces and inwardly of said permanent magnet, a shaft journalled forrotation in said base member, and a rotor member formed of magneticmaterial having radially outwardly extending teeth driven by said shaftrelative to said magnetic assembly.

7. An ignition timer comprising, a base member, a timing plate shiftablerelative to said base member, a vacuum unit for shifting said timingplate, a magnetic assembly carried by said tiiming plate including apermanent magnet and a coil winding, spacer means formed of nonmagneticmaterial spacing said magnetic assembly from said timing plate, a shaftjournalled for rotation in said base member, and a rotor formed ofmagnetic material rotatably driven by said shaft and swinging in closeproximity relative to said magnetic assembly whereby pulses of voltagesare induced in said coil winding as said rotor rotates.

8. An ignition timer comprising, a base member, said base member havinga central bore, a bearing fitting within said bore, a shaft journalledfor rotation in said hearing, a timing plate journalled for rotation ona portion of said bearing, a vacuum unit for shifting said timing plate,a magnetic assembly carried by said timing plate including a fluxgenerating means and a coil winding, and a rotor rotatably driven bysaid shaft relative to said magnetic assembly for causing pulses ofvoltage to be induced in said coil winding as said rotor rotates.

9. An ignition timer comprising, a base member, a shaft journalled forrotation in said base member, a timing plate shiftable relative to saidbase member, a vacuum unit for shifting said timing plate, a magneticassembly carried by said timing plate including a permanent magnet and acoil winding, a rotor member formed of mag- $3 netic material rotatablydriven by said shaft and swing ing in close proximity relative to saidmagnetic assembly to cause pulses of voltage to be induced in said coilwinding as said rotor rotates, a second rotor member formed ofinsulating material carrying an electrical contact, a distributor capsupported by said base member and enclosing said magnetic assembly andsaid second rotor, said distributor cap having contact means cooperatingwith the electrical contact carried by said second rotor.

10. An ignition timer comprising, a base member, a magnetic assemblysupported from said base member including a permanent magnet and a coilwinding, a shaft journalled for rotation in said base member, a rotormember formed of magnetic material rotatably driven by said shaftrelative to said magnetic assembly, centrifugal advance mechanism drivenby said shaft for adjusting said rotor member relative to said shaft, asecond rotor member formed of insulating material enclosing saidcentrifugal advance mechanism and carrying an electrical contact, and adistributor cap carried by said base member including contact meanscooperating with the electrical contact carried by said second rotor.

11. An ignition timer comprising, a base member, a magnetic assemblysupported from said base member including a permanent magnet and a coilwinding, a shaft journalled for rotation in said base member relative tosaid magnetic assembly, a rotor formed of magnetic material rotatablydriven by said shaft and swinging in close proximity relative to saidmagnetic assembly to cause pulses of Voltages to be induced in said coilwinding as said rotor rotates, and a centrifugal advance mechanismpositioned above said magnetic assembly for adjusting said rotorrelative to said shaft in accordance with the speed of rotation of saidshaft.

12. An ignition timer comprising, a base member, a magnetic assemblyincluding a permanent magnet and a coil winding carried by said basemember, a shaft journalled for rotation in said base member, a rotormember fromed of magnetic material rotatably driven by said shaft andswinging in close proximity relative to said magnetic assembly forcausing pulses of voltage to be induced in said coil winding as saidrotor rotates, a first plate member connected with said shaft, 21 secondplate member connected with said rotor, and flyweight means journalledfor swinging movement on one of said plate member and engaging the otherplate member for ad 6 justing said rotor member relative to said shaftin accordance with the speed of rotation of said shaft.

13. An ignition timer comprising, a base member, said base member havinga central bore, a bearing in said central bore, a shaft journalled forrotation in said bearing, a timing plate journalled for rotation on aportion of said bearing and engaging an upstanding portion of said basemember, a vacuum unit for adjusting said timing plate, a magneticassembly carried by said timing plate including a permanent magnet and acoil winding, and a rotor member formed of a magnetic material driven bysaid shaft relative to said magnetic assembly whereby pulses of voltagesare induced in said coil Winding as said rotor rotates.

14. An ignition timer comprising, a shaft, a timing plate adjustablerelative to said shaft, a magnetic assembly fixed to said timing plateincluding a pole piece formed of magnetic material, a coil winding and apermanent magnet, a rotor member formed of magnetic material rotatablydriven by said shaft and rotatable with respect to said magneticassembly, said rotor member forming part of a magnetic circuit whichlinks said coil winding and which includes said pole piece and saidpermanent magnet, said pole piece and rotor member having edges whichdefine a varying air gap as said rotor member rotates relative to saidmagnetic assembly whereby the reluctance of said magnetic circuit isvaried as said rotor member rotates.

15. The ignition timer according to claim 14 wherein a vacuum controlunit is provided for adjusting the timing plate relative to the shaft.

16. The ignition timer according to claim 14 wherein a centrifugalmechanism is provided for adjusting the rotor member relative to theshaft.

17. The ignition timer according to claim 2 where the flux generatingmeans is a permanent magnet.

18. The ignition timer according to claim 3 where the flux generatingmeans is a permanent magnet.

19. The ignition timer according to claim 8 where the flux generatingmeans is a permanent magnet.

References Cited by the Examiner UNITED STATES PATENTS 2,071,573 2/37Randolph et al 3 l0-68.4 2,824,245 2/58 Trevitt 3 lOl 08 2,872,537 2/59Hartzell et al. 200-31 MILTON O. HIRSHFIELD, Primary Examiner.

1. AN IGNITION TIMER COMPRISING, A BASE MEMBER, A TIMING PLATE SUPPORTEDBY SAID BASE, A PERMANENT MAGNET AND COIL WINDING SUPPORTED BY SAIDTIMING PLATE, POLE PIECE MEANS FORMED OF MAGNETIC MATERIAL ENGAGINGOPPOSITE ENDS OF SAID PERMAMENT MAGNET AND SAID COIL WINDING, A SHAFTROTATABLE IN SAID BASE, AND A ROTOR FORMED OF MAGNETIC MATERIAL CARRIEDBY SAID SHAFT ADJACENT SAID POLE PIECE MEANS, SAID ROTOR MEMBER HAVINGIN AIR GAP FORMED BETWEEN IT AND ONE OF SAID POLE PIECE MEANS AS ITROTATES.